I haven't, but I don't see any reason why you couldn't double it. I'm not sure I'd triple it, though. If you do double the recipe, be sure to stir the ketchup thoroughly while it's cooking, especially while you're reducing it to thicken it, to keep the bottom from scorching. It will take longer to reduce the larger volume, so the chances of scorching increase. You could also divide the cooked mixture, before reducing, into two smaller pans, which you'd cook down at the same time. That will cut down on the total time at the end. Have fun!! ;o)

You're welcome! I've been canning for 25+ years, during which time I've (i) worked full-time and raised a family, so time is always "of the essence," and (ii) had many opportunities to develop workarounds of all kinds, like this one. I'm so glad you like the ketchup! We use it on grilled meats, especially savory/garlicky sausages, and for glazing old-fashioned hams . . . . .;o)